Does Blood Glucose Monitor Affect Ghusl Validity?
| Fatwa #2291 | Category: Tahaarah (Purity) | Country: Zambia | Date: 31st March 2026 |
| Fatwa #2291 | Date: 31st March 2026 |
| Category: Tahaarah (Purity) | |
| Country: Zambia | |
Question
Assalamu Alyakum,
I am writing with deep concern and would sincerely appreciate a clear ruling according to the Ḥanafī madhhab, as this matter is causing me significant anxiety.
I am diabetic, with a condition that is described as a combination of Type 1 and Type 2 diabetes. For the past 7 years, I have been using a continuous blood glucose monitoring system called FreeStyle Libre. This is a small sensor that is inserted under the skin of my upper arm and continuously records my blood glucose levels 24/7. My medical team depends on this detailed data to monitor patterns and adjust my insulin dosage. My diabetes is currently well controlled using this method.
Each sensor works for 2 weeks, and I receive 2 per month. Once applied, it cannot be removed and reapplied. If I were to take it off, I would have to replace it with a new sensor.
Because the sensor adheres to the skin and covers a small area, water does not reach the skin directly beneath it during ghusl. My question is: would my ghusl be valid in this situation? I am extremely worried about the validity of my purification and prayers.
If using this device presents a problem from a fiqh perspective, the only alternative would be to return to finger-prick testing. However, that method provides only isolated snapshot readings at the moment of testing, rather than continuous and comprehensive data. As a result, it does not offer the same level of insight into daily fluctuations in blood glucose levels.
Although I have not undertaken a detailed comparison with my medical team, this continuous monitoring system has been relied upon for years to guide precise insulin adjustments and maintain stable control. I am therefore genuinely concerned that reverting to finger-prick testing alone could compromise the quality of my glucose management and, in the long term, negatively affect my health.
JazakAllah Khayrun
Answer
In the Name of Allah, the Most Gracious, the Most Merciful.
As-salāmu ‘alaykum wa-rahmatullāhi wa-barakātuh.
Purification laws in Shari’ah are considered sacred and rightfully so, as without them, no ibadah is acceptable. These laws are only suspended due to necessity.
The sensor in reference is attached in such a manner that a portion of one’s skin is covered by the sensor. It is also easily removable. The sensor is also marketed as being water resistant. If it is possible to ascertain from manufacturer, one should do so, as if the sensor turns out to be such that it allows water to touch the skin underneath it, it will be permissible to use. However, if the sensor is such that it does not allow water to touch the skin, then one’s ghusl/wudhu will remain invalid.
We understand that diabetes comes with certain challenges in one’s life. However, as previously stated, the laws of purification are lifted only if sufficient cause is found, necessity. In the enquired situation, alternative methods of tracking one’s blood sugar exist and prove to be ‘adequate enough’ to maintain one’s health. The sensor appears to be a ‘more convenient’ method of doing so. Granted, it provides additional benefits, however, these would not cross the realm of necessity.
Perhaps in extreme cases, where a medical expert insists on such a sensor due to one’s condition, the ruling would be affected. However, for general diabetics, this necessity is not found.
And Allah Ta’āla Knows Best
Mufti Bilal Pandor
Concurred by
Mufti Muhammad Patel
Darul Iftaa Mahmudiyyah
Lusaka, Zambia